Gilmore a World War II veteran, died of natural causes on 25 September (10) in Irvine, California.
He started his lengthy career as a U.S. radio announcer for hit shows including Amos 'n' Andy, The Sears Radio Theater and Red Ryder, before turning his attentions to TV and film.
On the small screen, he lent his voice to programmes including The George Gobel Show, An Evening With Fred Astaire and Highway Patrol. He also appeared on The Mary Tyler Moore Show, The Waltons and Dragnet.
His film career took off in the 1950s and '60s, when his voice could be heard in trailers and documentaries including It's a Wonderful Life, Rear Window, Vertigo, War of the Worlds, Bye Bye Birdie and White Christmas.
Gilmore served as the national president of the American Federation of Television and Radio Artists from 1961 to 1963 and helped found the Pacific Pioneer Broadcasters.
He taught announcing at the University of Southern California and co-authored Television and Radio Announcing.
Gilmore is survived by his wife of 72 years, Grace, two daughters, two grandchildren and four great-grandchildren.